An inverter driving device applies an electric current to a motor to control the operation of the motor. It is desired for such an inverter driving device to control a motor current for appropriately controlling the magnitude and phase of the voltage applied to the motor and, additionally, reducing the number of current sensors that detect the motor current, thus detecting the motor current using a detected value of the direct bus current of the inverter.
PTL 1 discloses a system for detecting an instantaneous value of the direct bus current to determine an offset amount of the direct bus current detecting circuit. In particular, PTL 1 discloses a technique to detect a value of the direct bus current as an offset compensation amount at timing (vector V0) in a period during which one of high-potential side and low-potential side switching elements of the inverter is subjected to off-operation.